What To Do

Boil eggs in water with a tea bag for 7 minutes to make a hard boiled egg. Let the eggs cool completely before using them for this science project. The tea will stain the egg brown. After talking about the importance of taking good care of our teeth or reading a preschool dental health book, give each preschool a tooth brush and show them how to "brush" the egg. Tell them that the hard shell of the egg is just like the enamel that we have on our teeth. Let them know that our teeth can be stained by the things that we eat and by letting plaque grow on our teeth because we have not brushed well enough.

The brown stains will disappear as the preschoolers brush. Tell the preschoolers that when we brush our teeth we make sure they will stay nice and clean and white.

Variation

This preschool science activity can also be done by cooking hard boiled eggs, letting them cool, and soaking them overnight in a bowl of soda in the fridge.

More About Preschool Dental Health

Taking Care of Teeth - Preschool Dental Health

February is Dental Health Month. Take the opportunity to teach preschoolers about the importance of good dental health. This curriculum theme will have preschoolers motivated to take better care of their teeth. Fabulous science activities will show preschoolers what really happens to their teeth if they don't take care of them.

Preschool Book Review - Big Shark's Lost Tooth

Chomp is a lemon shark who has just lost a tooth, but he lives deep in the ocean. How will the Tooth Fairy ever find him? The fantastic illustrations and undersea setting bring a new dimension to the story of the Tooth Fairy.

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Hi! I'm Rachel Lister, the Preschool Education writer at PreschoolRock.com. I live in Utah with my husband and two beautiful boys. When my oldest son was born, I quit my teaching job and opened a home daycare and preschool. I love to help preschoolers learn about the world around them. They make life interesting and I can't imagine doing anything different. If you have any ideas, suggestions or comments, feel free to contact me.

Helpful Tips for Parents

• Use mathematical language all day: "more than," "less than," "half," "equal," "twice as much." Incidental math vocabulary builds the conceptual foundation formal math builds on.

• Avoid academic pressure before age 5. Preschool children's brains are not developmentally ready for formal academic instruction, and premature pressure backfires.

• Answer "why" questions fully and honestly. A child who gets real answers to their questions develops deeper curiosity than one whose questions are dismissed or oversimplified.

• Screen learning (educational apps and videos) supplements but never replaces human interaction as a teaching medium. Learning happens most efficiently in social, conversational contexts.

Frequently Asked Questions

What is the role of technology in preschool education?

High-quality educational apps and programs (PBS Kids, Khan Academy Kids, Starfall) used in limited, adult-co-viewed sessions can supplement preschool learning. However, interactive human experiences (conversation, shared book reading, hands-on experimentation, social play) remain far superior as primary learning modes. Screen-based learning is most effective when it is: co-viewed with an adult, limited to 30–60 minutes per day, followed by extension activities in the real world (after a nature app, go outside), and consistently educational rather than commercial.

How do I support a gifted preschooler who seems to need more than peers?

Gifted preschoolers benefit from depth rather than acceleration — instead of teaching next-year's content, provide deeper engagement with current concepts. A preschooler fascinated by numbers doesn't need grade-school arithmetic; they benefit from mathematical puzzles, spatial reasoning challenges, and mathematical exploration at their own depth. Social-emotional support is equally important: gifted preschoolers often have asynchronous development (advanced intellectually but emotionally typical for their age) and need appropriate peer interaction alongside intellectual challenge.

Related reading: See also our read-aloud guide and our kindergarten readiness guide for more ideas on this topic.

🎓 Skills Your Child Will Develop

• 🔢 Early Numeracy — Hands-on counting, sorting, measuring, and pattern work develops the number sense and mathematical reasoning that formal arithmetic will later build on — and preschool numeracy is one of the strongest predictors of later math achievement.
• 🌐 World Knowledge — Background knowledge about the world dramatically accelerates reading comprehension — children who know more understand more of what they read — making every content-area learning experience a literacy investment.
• 😊 Love of Learning — Positive early learning experiences build a child's identity as a learner — and children who see themselves as curious, capable learners approach school with the engagement and resilience that matter more than any specific skill.
• 🧠 Memory & Recall — Remembering rules, retelling a story in sequence, and practicing skills to automaticity builds working memory and long-term recall — the cognitive foundation that learning in every subject depends on.

****This preschool science activity will give preschoolers a visual reminder to brush their teeth. As you are doing this activity, talk to preschoolers about how important it is to brush our teeth well. Once they see what it really means to brush our teeth they will want to have nice clean teeth and keep their teeth healthy by brushing at least 2 times a day.

What you need

eggs

bowls

toothbrushes

soda or tea